Reply #2: It would appear so

[OKIsItJustMe]

http://hosted.ap.org/dynamic/stories/U/US_ARKANSAS_EARTHQUAKES

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A major source of natural gas in Arkansas is the Fayetteville Shale, an organically-rich rock formation in north-central Arkansas. Drillers free up the gas by using hydraulic fracturing or "fracking" - injecting pressurized water to create fractures deep in the ground.

Ausbrooks said geologists don't believe the production wells are the problem, but rather the injection wells that are used to dispose of "frack" water when it can no longer be re-used. The wastewater is pressurized and injected into the ground.

"We see no correlation between natural gas production wells and earthquakes, but we haven't ruled out injection wells," he said, adding that if production wells were the cause, the earthquakes would be scattered all over the region underlain by the Fayetteville Shale formation and not in just one area.

Ausbrooks said the earthquakes are occurring in the vicinity of several injection wells.

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